The present invention relates to an apparatus for holding a printing medium in a printer, such as an ink jet printer, which can apply ink from ink jet nozzles onto the printing medium, such as a paper sheet, held on a drum rotating at a prescribed circumferential speed and thus rotating together with the drum and which can thereby perform printing.
A so-called serial-type ink jet printer is known. In this printer, the nozzle units for respective colors are repeatedly moved back and forth in the line direction. While moving along each line, the nozzle units print one line on a printing medium. Every time one line is printed, the printing medium (an ordinary paper sheet or an OHP sheet) is fed forward by line one.
An ink jet printer is known in Japanese Patent Application No. 8-296959 filed by the assignee of the present patent application. This ink jet printer can effect printing at a speed much higher than the serial-type ink jet printer and can continuously print a number of pages. Further, it can be much smaller than so-called laser printers.
In order to increase the printing speed of an ink jet printer, it is necessary to hold a printing medium quickly and reliably on the circumferential surface of the drum, while keeping the drum rotating, that is, without stopping the drum. It is also necessary to release the printing medium from the drum after the printing has been accomplished.
The object of the present invention is to provide an apparatus for use in a printer, which can hold a printing medium on the drum quickly and reliably and can release the medium from the drum after printing has been carried out.